The Daily Mail retracted its story in a posting on its website late on Thursday.

"To the extent that anything in the Daily Mail's article was interpreted as stating or suggesting that Mrs. Trump worked as an 'escort' or in the 'sex business'... is hereby retracted, and the Daily Mail newspaper regrets any such misinterpretation."

Melania warned the newspaper and other media organisations that she would take legal action on August 22.

Trump's lawyer Charles Harder branded the reports "outright lying."

"These defendants made several statements about Mrs Trump that are 100% false and tremendously damaging to her personal and professional reputation," he said.